In the last decade two monumental public works campaigns — a cleanup of Boston Harbor and the infamously protracted Big Dig — were completed that were expected to set the stage for a 21st century transformation of downtown Boston. In April 2008, a city agency produced a summary of 250 construction projects that were planned or had already been approved. Fourteen months later, a quarter of the projects from that $12 billion list are being built, and three of the largest are along the city’s waterfront.